Multiple family members (mother - daughter/son) is a documented
phenomena in ME. I'm guessing it's transmission of XMRV in the womb?

My mother has ME, and me also. (She has a blood transfusion before I was born). Over the nearly 2 decades I have had the disease.
I do hear of multiple girls in the family having ME.
E.g it's not ultra rare, but rare for me to see or hear this on news broadcasts.

It obviously happens for a reason.

Dr Judy says XMRV is infectious, (obviously) as it's a retrovirus.

I am very suspicious we are born with it, and mother passes it in her blood.
There are practically no Father - Son/Daughter cases of ME.

Another possibility is mitochondria. Mitochondria is passed on by mother.
XMRV infects mitochondria I hear - hence the exhaustion.

Well my husband and I both have ME/CFS and so does one of my sisters-in-law, so a genetic link between my husband and sister obviously but none with me. And we all 3 fell in in 1980/81.

I came down with mono in Feb 1980, my husband came down with a weird flu like illness a couple of months later anmd I can't remeber exactly when my SIL came down with mono but the same year I think or the next. At the end of 1980 I also came down with an enterovirus, coxsackie b3. However we didn't have uch contact with my SIL, she lives at the other end of the UK so we only saw her breifly on holidays, so not living together longterm.

Strangely my husband and I both recently had some genetic testing done and the doc commented on how weird it was that our liver detox genes were similar but different but amounting to the same thing, appreciable problems in liver detox and also we had oxidative stress and reduced ability to deal with pesticides. We also both had problems with methylation cycle genes, so again detox problems and of course Rich says that methylation cycel neds to be working right to hold latent viruses in check.

We were then tested for pesticides with a fat biopsy and found to have 3-4 times the "normal" (normal would be none) level of organochlorine pesticides, lindane, (and another one whose name I can't remeber) which is immunosuppressive, neurotoxic, screws up the endocrine systems carcinogenic etc etc.

So I wonder if environmental things like poor detox leading to chronic buld up of pesticides etc and also of course heavy metals can also help to trigger a virus like XMRV?

So you have a genetic component, a chemical environmental component, viral triggers like mono and emteroviruses and all of these or a combination of some leads to CFS?

Our story is, I think, interesting when we talk about spousal transmission. I had CFIDS beginning in high school, with my most serious crash five years later. I did not know my husband then. I was ill again a few years ago when we were married and was successfully treated with antivirals by Dr. Peterson. My husband was diagnosed with mono a year and a half ago, and never got better. I had always assumed families who got sick had had the same virus sweep through, but in our situation it was not the case.